<!DOCTYPE html>
<html>
<head>
    <title>全局变量检测</title>
</head>
<script type="text/javascript">
    
    window.onload = function () {
        setInterval(function() {
            debugger;
            var target = document.body;
            target.appendChild(document.createElement("div"));

        }, 4000);
    }
</script>
<body>
    <div class="mutation-observer-wrap">

    </div>
    <script type="text/javascript" src='./mutation.js'></script>
</body>
</html>